1. Field of the Invention
The present invention relates generally to ink cartridges and inkjet printers which use such ink cartridges.
2. Description of Related Art
A known inkjet recording system includes an inkjet recording apparatus and a plurality of ink cartridges which are mounted side by side to a mounting portion of the inkjet recording apparatus. An ink supply opening is formed at one surface of the ink cartridge, and an ink supply needle is provided in the inkjet recording apparatus and is inserted through the ink supply opening when the ink cartridge is mounted to the inkjet recording apparatus, which causes ink within the ink cartridge to be supplied to inkjet recording apparatus. The ink cartridge includes a case and a bag positioned within the case. The bag has a port for supplying ink within the bag to the outside of the ink cartridge, and the port is aligned with the ink supply opening. A lid, a valve, and a spring are provided within the port, such that the spring urges the valve to contact the lid. Specifically, when the valve contacts the lid, fluid communication between the inside of the bag and the outside of the ink cartridge is prohibited, and when the ink supply needle pushes the valve against the urging force of the spring, the valve separates from the lid, the inside of the bag and the outside of the ink cartridge are in fluid communication with each other.
Ink adheres to the ink supply needle after the ink supply needle is inserted into the ink cartridge through the ink supply opening. The ink which adheres to the ink supply needle adheres adjacent to the ink supply opening when the ink cartridge is removed from the mounting portion. The ink may drip from the ink supply opening onto the mounting portion. When the ink drips from the ink supply opening onto the mounting portion, the mounting portion becomes dirtied. In addition, ink may drip from the ink supply needle onto the mounting portion. After the mounting portion becomes dirtied, when a new ink cartridge is mounted to the mounting portion, the new ink cartridge also becomes dirtied. When the new ink cartridge is removed from the mounting portion, a hand of user also may become dirtied. Moreover, when the ink supply needle is removed from the ink supply opening, the spring pushes the valve back toward the ink supply opening. Therefore, ink is pushed by the valve toward the ink supply opening, and a relatively large amount of ink may be pushed out of the ink supply opening.
Another known ink cartridge includes an ink supply portion protruding from one surface of the ink cartridge. An ink supply opening is formed at the end of the ink supply portion. Ink may also drip from the ink supply opening of this type of ink cartridge onto a mounting portion of an inkjet recording apparatus.